Albumin-STING Nanocomplex Reprograms HSPCs to Antitumor Neutrophils with Enhanced MHC I Antigen Presentation for Cancer Immunotherapy

Tumor-associated immunosuppressive neutrophils, termed myeloid-derived suppressor cells (MDSCs), compromise cancer immunotherapy. They can be pathologically programmed as early the hematopoietic stem and progenitor cell (HSPC) stage by suppressing interferon signaling. Reprogramming HSPCs toward antitumor neutrophils through the stimulator of interferon genes (STING) activation offers a promising therapeutic strategy. Here, we demonstrate that an albumin-STING nanoagonist (Nano ZSA-51D) reprograms HSPCs to generate antitumor neutrophils, enhancing MHC I-mediated CD8 T cell immunity. Nano ZSA-51D activates STING-interferon signaling in HSPCs, promoting their expansion and differentiation toward granulocyte-monocyte progenitors via STING-NF-{kappa}B-IL-6 signaling. It further reprograms neutrophils into CD14ICAM-1+ subset through STING-NF-{kappa}B-TNF- signaling, enhancing tumor infiltration. These neutrophils upregulate interferon signaling and MHC I antigen presentation, boosting tumor-specific CD8 T cell responses. Adoptive transfer of Nano ZSA-51D-reprogrammed neutrophils with -PD1 therapy achieves complete colon tumor remission. Our findings provide a novel strategy to reprogram HSPCs toward antitumor neutrophils and highlight the potential of early interventions at HSPC stage to rewire neutrophil fate for cancer immunotherapy.